Question

Is y=2x-9 a direct variation and if so, what is the constant?

Answer 1

`2-9/x`

Explanation:

Formula for direct variation,

`y=kx`, where `k` is the constant.

`y=kx=2x-9`
`kx=2x-9`

Hence, the constant is,

`k=(2x-9)/x`
`k=2-9/x`

Check:
graph{y=(2-9/x)(x) [-32.47, 32.5, -16.23, 16.24]}